Fire extinguisher



July 26, 1960 c. H. BARNES FIRE EXTINGUISHER Filed Nov. 8, 1957 4 Al 4 \\\\\\s I INVENTOR CHARLES H. BARNES BY 9 WM CW ATTORNEY 2,946,389 7 FIRE EXTINGUISHER Charles H. Barnes, Wilmington, Del., assignor to Specialties Development Corporation, Belleville, N.J., a corporation of New Jersey Filed Nov. 8, 1957, Ser. No. 696,013

6 Claims. (Cl. 169-31) The present invention relates to fire extinguishing apparatus, and, more particularly, to portable fire extinguishers containing a liquid fire extinguishing agent which is discharged therefrom by a pressurized fluid released from a cartridge.

Fire extinguishers of the foregoing type essentially comprise a receptacle containing the liquid agent with an air space above it, a syphon tube extending to the lower end of the receptacle, a discharge hose connected to the upper end of the syphon tube, a cartridge arranged for discharging pressurized fluid into the air space, and manually operable mechanism for effecting release of the pressurized fluid.

It has been found that the air in the space above the liquid agent expands with an increase in temperature and exerts a pressure on the agent which is effective to expel a portion thereof by way of the syphon tube and the discharge hose. Several cycles of heating and cooling may cause a substantial quantity of the liquid agent to be expelled without positive indication of such loss unless the extinguisher is weighed frequently.

To preclude this danger, it has been common practice to provide an additional control in the form of a valve at some point in the discharge tube. In the hands of the inexperienced, confusion may result in the delay of opening such a valve thus allowing the fire to make headway and thereby be more difficult to extinguish. Also, a relief valve has been provided to equalize small pressure differences while sealing against those pressures associated with deliberate discharge. Owing to its inherent requirement for extreme sensitivity, such a valve is prone 'to failures of a mechanical nature which may be caused by dirt or damage.

Accordingly, an object of the present invention is to provide a fire extinguisher of the foregoing character having a pressure equalizing passage which is both practical for manufacture and reliable in operation and which will prevent the loss of extinguishing agent due to ambient temperature changes.

Another object is to provide such a fire extinguisher which is both economical to manufactureand convenient to service.

Other and further objects of the invention will be obvious upon an understanding of the illustrative embodiment about to be described, or will be indicated in the appended claims, and various advantages not referred to herein will occur to one'skilled in the art upon employment of the invention in practice.

A preferred embodiment of this invention has been chosen for purposes of illustration and description and is shown in the accompanying drawing wherein:

Fig. 1 is a fragmentary side view of a fire extinguisher in accordance with the invention, partly in section and partly in elevation.

Fig. 2 is a fragmentary enlarged sectional view illustrating the valve of the fire extinguisher in detail.

Referring to the drawing in detail, a fire extinguisher nited rates Pate ice is shown which essentially comprises a container or receptacle 6 for a liquid fire extinguishing agent, discharge conduit means 7, a cartridge 9 containing a pressurized fluid and a valve 10 for effecting release of the fluid from the cartridge.

As shown in Fig. 1, the container 6 has a generally cylindrical body 11, a closed lower end, and a top 12 provided with a central spud or tubular element 14 formed with an inwardly inclined seat or shoulder 15 at its upper end and provided with an offset spud 16. The lower end of the central spud '14 extends into the container and is formed with an aperture 17 in the wall thereof.

The discharge conduit means 7 includes a syphon tube 19 attached to the lower end of the spud 16 and extending to the proximity of the bottom of the container and having a conventional wire mesh strainer 18 inserted at its lower end, and a hose 20 having one end attached to the upper end of the spud 16 and having a discharge nozzle 21 attached to its other end.

As shown in Figs. 1 and 2, the cartridge 9 comprises a tubular body 24, a lower end closure 25, including a fixed plug 26 and a removable plug 27, and a generally cup-shaped upper end closure 29 extending partially into the body 24 and having a weakened puncturable central portion 30, a tubular zone 31 disposed outwardly of the body 24 formed with a plurality of apertures 32 and a flared flange 34 adapted for pressure tight sealing upon the seat 15. Ample clearance is provided between the bore of the central spud 14 and the exterior of the tubular cartridge body 24 and the tubular zone 31 for unrestricted fluid flow from the interior of the cup-shaped upper closure 29 through the apertures 32 into the air space above the liquid in the container.

The valve 10, shown in detail in Fig. 2, has a body 37 formed with a frusto-conical lower end 38 adapted for sealing engagement with the flange 34 on the cartridge. A nut 40 is swivelly secured ot the valve body by means of a ring and is threadedly secured to the spud 14. A central bore 41 extends through the valve body which has an apertured partition 42 at about its mid-point.

A puncturing pin 45 is disposed within the bore 41 and has a flange 46 intermediate its ends and abutting the lower surface of the partition 42 which is held in position by a compression spring 47 confined within the lower portion of the bore 41 by a retainer 49. The portion of the pin, which is movable within the aperture of the partition 42, is of a reduced diameter and is joined by an upwardly and outwardly extending tapered section 48 to an enlarged diameter section 53 at the upper portion of the pin. A gasket such as an O-ring 54 fits loosely about the reduced diameter of the pin 45, and is held in abutment against the upper surface or shoulder of the partition 42 by a compression spring 51 which is confined within the bore by an upper retainer 52. The pin 45 passes through the upper and lower retainers in very loose fitting relationship, and the flange 46 is appropriately milled to thus provide an unrestricted fluid flow passage from the interior cavity of the upper cartridge closure 29 to the atmosphere.

A carrying handle 55 and an operating lever 56, are attached to the valve body 37. The operating lever is adapted to bear against and depress the puncturing pin 45. A grommet 57 is mounted within the free end of the operating lever and is adapted for retaining the nozzle 21 when not in use.

Thus, it will be seen that an unrestricted path, although devious, is always available to relieve any pressure due to an ambient temperature increase to which the extinguisher may be subjected in normal standby. Commencing with the annular passageway between the cen- 3 tral'spud 14 and the cartridge body 24, flow is permitted through the apertures 32 and between the puncturing pin 45 and, in sequential order, the lower retainer 49, the aperture of the partition 42' and the upperretainer 52.

'In operation, the noiz'lzle is removed from its retainer 57, thus'treeingthe' operating lever 56. Depression of the operating lever drives the puncturing pin 451dow'nwa'r'dly, fir'st'to' effect a seal between the O'-ring 54 and the enlarged diameter section 53 of the pin, and second to rupture th e weakened centralsection 30' of the upper partridge closure 29. Momentarily, the gas releasedinitially travels upwardly along" the puncturing pin through the partition aperture thus torcingthe O-ring to further cornpress the upper spring '51 and to maintain an eflective seal as lon g'as pressure -'remains. The gas flows out off the cartridge through the apertures 32 and downwardly through the annular opening between the cartridge and central spud' 3 5 to 'develop 'a 'drivingpres'surein the air cavity over the extinguishing agent'tnus discharging 'the agent through the discharge'conduit means to the atmosphere.

From the foregoing description it will be seen that the present invention provides a simple and practical means for venting fir'e'ex tinguishers of the classldescribed.

As various changes may'be made inthe form, construction and arrangement of thepartshercin," without depart ing' from'the spirit and scopeof the invention and witheut sacrificing-any of its advantages, it is to'be' understand;

that all matter herein is to be' interpreted as illustrative and not in any limiting sense.

application SerialNol 543,063, filed October 27, 1955, now abandoned.

l. A fire extinguisher comprising a receptacleoroontaining a fire extinguishing" liquid, discharge conduit means for said receptacle including a syphon tube, a tubular spud secured to said receptacleterminating in'a shoulderexternally of said receptacle, and extending downwardly into said receptacle to about" the normal filling head including meansfor puncturing said closure means. 7

2. A fire extinguishercom'prising a receptacle for conv 4 bore to the atmosphere, and means for sealing said venting passageway coincident with the puncturing of said closure means.

3. A fire extinguisher comprising a receptacle for containing a fire extinguishing liquid, discharge conduit means for said receptacle including a syphon tube, a tubular spud secured to said reeeptaole terminating in a shoulder externally of said receptacle, a cartridge for containing a fluid under pressure and extending downwardly spud} through said bore to the atmosphere, said bore be This application is a continuationdn-part' oi copending taining a fire extinguishing' liquid, discharge conduit 7 means for said receptacle including a syphon tube, a tubular'spud secured to' said receptacle terminating in a shoulder externally ofsaid receptacle, a cartridge for containing a fluid under pressure and extending downwardly adjacent said spud to the atmosphere, a pin mounted' in said bore for puncturing said "closure means normally providinga venting passageway from said spud through said ingffornredkvith a shoulder and said pin having a reduced sectionadjacen't said shoulder, and a gasket movably mounted on" said shoulder and encircling said reduced section and adapted to move into engagement with saidpinabove said reduced section inresponse to fluid pres sure and thereby seal said vent.

4; A fire extinguisher according to claim 3, including as'pring' insaid here for urging said gasket on said shoulder.

e 5'. A fireextinguisher comprising a receptacle for containing afire extinguishing liqnidhaving means providing an ;opening at the upper end thereof; diseharge'conduit means for'said receptacle including a syphon tube within said receptacleextend-ing from the upper end to adjacent t-the" lower endthereof; a cartridge for containing a fluid tween its upper end and said sealing rne ans in fluid flow communication with theinterioroii saidreeeptacle; a discharge control head secured to said opening rneansofsaid receptacle, said head having a boreextending from within saidtubularcartridge portion to the atmosphere;

"means carried by said head for rendering said cartridge sealing means ineffective including a pin mounted in said bore t'o normally provide-a vent from said tubular carto sealsaidivent coincident with the-operationof said means for rendering said sealing-means ineffective-- 6; Afir extinguisher according to claim 5, wherein said vent and said means operable to seal the samein clude a shoulder in said 'lgore, a-gasket on said shoulder, a

reduced pinls'ection encircled by said gasket and a pin 'section above said reduced section adapted to engage said gasket;

References Cited in the file of this patent usua sures PATENTS 995,978 McCaslin June 20, 191 1- 1,638;0l7- Raus V Aug. 9,"192'7 2,385,449 Koehler Sept. 25, 1945 1 6 3 l en sept- 6 1 5 '5 Au tin ,-jle,,-..,, .h--V- June 4, i 

